The predictions for the charm production strongly depend on the
modelling of the partonic content of the proton
 [1]}. In particular, the contribution of the charm
- initiated process is directly associated with the description of the
extrinsic and intrinsic components of the charm content in the proton
(for a recent review see, e.g. Ref. [2]}).
Differently from the extrinsic charm quarks/antiquarks that
are generated perturbatively by gluon splitting, the intrinsic
one have multiple connections to the valence quarks of the proton
and thus is sensitive to its nonperturbative structure
[3]}, [4]}, [5]}.
The presence of an intrinsic component implies a large enhancement
of the charm distribution at large \(x\)  (\(> 0.1\) ) in comparison to
the extrinsic charm prediction. Moreover, due to the momentum sum rule,
the gluon distribution is also modified by the inclusion of intrinsic
charm. In recent years,
the presence of an intrinsic charm (IC) component have been included in
the initial conditions of the global parton analysis [6]}, [7]},
the resulting IC distributions that are compatible with the world
experimental data.
However, its existence is still a subject of intense debate
[8]}, [9]}, mainly associated with the amount of intrinsic
charm in the proton wave function, which is directly related to
the magnitude of the probability to find an intrinsic charm or anticharm
(\(P_{ic}\) ) in the nucleon.
